TrekSta Sync Trail Running Shoe - Men's Synthetic NestFIT system cradles your feet, accounting for every contour as it follows the natural flow and design of the foot. Upper, insole, midsole, and outsole come together like never before. HyperGrip sole provides superior traction. Ultralight EVA midsole compliments the insole for a naturally balanced and stable foundation. Highly breathable mesh upper keeps your feet cool and dries quickly. IST sole: Anatomical sensor zones recognize and respond to terrain for a pure connection between runner and trail.